When I try to send a file as a response from the published Web service in Adeptia, it throws the Fault
"com.adeptia.indigo.utils.XmlException: Content is not allowed in prolog"
The file you want to send in response has JSON in it not XML. SOAP based Web Service works in XML format only.
If you want to send JSON in Web Service response try using Rest Provider.
For more information on Rest provider refer the below link: